LMCV — failed Hyperlane message replay mints dPRIME repeatedly

Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: 50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo. Standalone Foundry PoC and full write-up: 50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo_exp in the evm-hack-registry mirror.

Vulnerability classes: vuln/bridge/replay · vuln/bridge/missing-validation · vuln/logic/state-update

Reproduction: Fully local, cheatcode-free synthetic. Run forge test -vvv in this folder.

Key info#

Field	Value
Protocol	LMCV
Finding	AuditVault 50682
Impact	High
Reproduction	Local synthetic; no mainnet fork
Vulnerable contract	See `test/50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo.sol`
Compiler	Solidity 0.8.24

TL;DR#

A failed Hyperlane transfer remains in failedMessages after retry succeeds. The exact same origin, recipient, and nonce can be retried repeatedly, minting the amount again each time.

Vulnerable code#

The minimized contract preserves the report’s blamed operation with an @> VULN marker in the synthetic.

Root cause#

retry reads the retained amount then mints it in a try block. Its successful branch emits ReceivedTransferRemote but never clears failedMessages. The retry is therefore not a one-time state transition.

Preconditions#

The relevant protocol integration is configured and holds the affected asset or retained message. No privileged bypass beyond the intended caller is required for the demonstrated broken path.

Attack walkthrough#

The local reproduction stores one 100-unit failed message, calls retry twice, and proves the recipient holds 200 dPRIME while the failed message still records 100.

Diagrams#

flowchart TD A["LMCV Hyperlane Connector failedMessages retained retry #1 mints 100 retry #2 mints another 100 recipient holds 200"] --> B["undefined"] B --> C["undefined"] C --> D["undefined"] D --> E["undefined"]

Impact#

The synthetic ends with an on-chain require proving the report’s concrete harm, rather than merely proving a function can be called.

Remediation#

Delete failedMessages[_origin][_recipient][_nonce] before the mint (or otherwise atomically mark it consumed). If mint can fail, preserve the entry only on failure.

How to reproduce#

BASH

cd /workspaces/RustroverProjects/audits/evm-hack-registry/50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo_exp
forge test -vvv

Sources#

AuditVault finding
Halborn assessment
Reduced local source: test/50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo.sol

Sources & further analysis#

Reproductions & code

Standalone PoC + full trace: 50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo_exp (evm-hack-registry mirror).
AuditVault finding: 50682-unlimited-minting-by-reusing-failed-hyperlane-messages-halbo.

Alerts & third-party analyses

Web3Sec X hacked database: search.
Rekt leaderboard: search.
Solodit incident search: search.

These dashboards index community alerts tweets, post-mortems, and independent write-ups. Reach them through the protocol name above to cross-check this reproduction against other analyses.

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